Fluoranthenes have attracted tremendous attention due to their unique optoelectronic properties and extensive applications.Although several synthetic methodologies have been developed for the preparation of fluoranthe...Fluoranthenes have attracted tremendous attention due to their unique optoelectronic properties and extensive applications.Although several synthetic methodologies have been developed for the preparation of fluoranthene derivatives,it is still unfavorable to functionalize the fluoranthene framework at different positions due to the relatively low selectivity and reactivity.Herein,a catalyst-free intramolecular[4+2]annulation between thiophenes and alkynes is developed towards the synthesis of fluoranthenes.Altogether 20 examples have been demonstrated using this method.Various functional groups can be precisely introduced into the fluoranthene skeleton at different positions by simply tuning the substituents on the thiophenes and alkynes.The conjugation of the fluoranthene can be facilely extended through different directions.Furthermore,the feasibility of this[4+2]annulation reaction is also investigated by density functional theory calculations.Therefore,this protocol provides not only a synthetic methodology towards fluoranthenes with substituents functionalized at different positions,but also an effective pathway to construct large polycyclic aromatic hydrocarbons containing fluoranthene moieties.展开更多
The cooperative catalysis of an achiral Lewis base and a chiral N-heterocyclic carbene(NHC)enables a highly enantioselective[4+3]annulation of benzoxazinanones with isatin-derived enals.DMAP serves as a nucleophilic L...The cooperative catalysis of an achiral Lewis base and a chiral N-heterocyclic carbene(NHC)enables a highly enantioselective[4+3]annulation of benzoxazinanones with isatin-derived enals.DMAP serves as a nucleophilic Lewis base to promote decarboxylation of benzoxazinanones,which leads to azaortho-xylylene intermediates that undergo[4+3]annulations with NHC-bound homoenolates.This method breaks the substrate scope limitation of transition-metal-catalyzed variants,thus a broader range of benzoxazinanones are tolerated,and provides a straightforward entry to enantioenriched spirooxindoles in high structural diversity.展开更多
Conventional reactive sites of ketones with aldehydes lie on the carbonyl andα-carbon positions,which lead to a wide range of classic reactions such as pinacol-coupling and aldol-type condensations.Herein,an unpreced...Conventional reactive sites of ketones with aldehydes lie on the carbonyl andα-carbon positions,which lead to a wide range of classic reactions such as pinacol-coupling and aldol-type condensations.Herein,an unprecedented reactive site of aromatic ketones toward aldehydes has been revealed by using earth-abundant manganese catalysis,which enabled the first deoxygenative[3+2]annulations of ketones and aldehydes through C–H activation affording isobenzofuran derivatives.Mechanistic studies give hints on the dual role of triphenylborane additive in the reaction,that is,promoting C–H activation as a transmetalation reagent and activating aldehydes as a Lewis acid.展开更多
Copper-catalyzed divergent annulations betweenα-diketones and alkynylα-diketones have been achieved,delivering a series of highly functionalized and biologically important cis-hexahydro-2Hcyclopenta[b]furan(HCPF)and...Copper-catalyzed divergent annulations betweenα-diketones and alkynylα-diketones have been achieved,delivering a series of highly functionalized and biologically important cis-hexahydro-2Hcyclopenta[b]furan(HCPF)and 2-hydroxydihydrofuran-3(2H)-one(HDFO)products with high levels of stereoselectivity under identical conditions.The protocol features the use of earth-abundant copper catalyst,mild conditions,shortening synthetic routes in constructing different molecular frameworks,and reducing the corresponding possible waste production.The substituents of the nucleophilicα-diketones play crucial roles in switching the reaction pathways.展开更多
Copper catalyzed enantioselective [4+2] annulations of D-A cyclobutanes and aldehydes have been developed. In the presence of a side arm modified chiral bisoxazoline (SaBOX) ligand, the [4+2] annulations proceeded...Copper catalyzed enantioselective [4+2] annulations of D-A cyclobutanes and aldehydes have been developed. In the presence of a side arm modified chiral bisoxazoline (SaBOX) ligand, the [4+2] annulations proceeded smoothly with a broad substrate scope. 22 examples were studied, leading to the corresponding products with various functional groups in 41%-99% yields with 〉99/1 dr and 90%-96% ee. The resulting product with two ester groups was mono-reduced, giving the corresponding product in excellent diastereoselectivity without loss of the enantiopurity.展开更多
In this paper, an efficient synthesis of cyclopentenyl ketones and cyclohexenyl ketones through tertiary phosphine catalyzed [3 + 2] and [4 + 2] annulations of 1,2-allenic ketones with activated alkenes has been dev...In this paper, an efficient synthesis of cyclopentenyl ketones and cyclohexenyl ketones through tertiary phosphine catalyzed [3 + 2] and [4 + 2] annulations of 1,2-allenic ketones with activated alkenes has been developed. Compared with published synthetic methods on cyclopentenyl ketones and cyclohexenyl ketones, the protocols developed in this paper have the advantages such as readily available starting materials, mild reaction conditions and high efficiency.展开更多
A mild and efficient dearomatic [3+2] annulation reaction of 3-nitro-7-azaindoles and Morita Baylis Hillman carbonates from isatins was developed catalyzed by DMAP, affording the corresponding polycyclic spirooxindol...A mild and efficient dearomatic [3+2] annulation reaction of 3-nitro-7-azaindoles and Morita Baylis Hillman carbonates from isatins was developed catalyzed by DMAP, affording the corresponding polycyclic spirooxindoles containing fused azaindoline architectures and vicinal quaternary centers in excellent yields(up to 96%) with high regio- and diastereoselectivity(dr 〉 19:1). Moderate enantioselectivity(79% ee) was obtained by employing a chiral DMAP-type Lewis base catalyst.展开更多
Me OTf-catalyzed formal[4+2]annulation of styrene oxides with alkynes to afford polysubstituted naphthalenes has been realized,which undergoes sequential electrophilic cyclization/ring expansion.A range of substrates ...Me OTf-catalyzed formal[4+2]annulation of styrene oxides with alkynes to afford polysubstituted naphthalenes has been realized,which undergoes sequential electrophilic cyclization/ring expansion.A range of substrates were tolerated in the formation of naphthalene derivatives with high regioselectivity in satisfactory yields.The reaction could also be carried out on gram scale.展开更多
in this work, the phosphine-catalyzed annulation reactions between modified allylic derivatives and polar 1,1-dicyano-1,3-dienes have been studied. In the catalysis of PPh3 (20 mol%), a [4 + 1 ] annulation reaction...in this work, the phosphine-catalyzed annulation reactions between modified allylic derivatives and polar 1,1-dicyano-1,3-dienes have been studied. In the catalysis of PPh3 (20 mol%), a [4 + 1 ] annulation reaction is realized between a series of l,l-dicyano-2,4-diaryl-1,3-dienes and ethoxycarbonyl-activated allylic acetate, producing polysubstituted cyclopentenes in modest to excellent yields. It is also observed that the substituents of both 1,3-dienes and allylic derivatives have a significant influence on the annulation mode: under the catalysis of PPh3 or PBu3 (20 mol%), regioselective [3 + 2] annulation products are formed from differently substituted substratcs.展开更多
Four types of unprecedented and chemodivergent reactions betweenα-diketones and alkynylα-diketones have been achieved under the catalysis of phosphine and Br?nsted base,respectively,leading to the rapid construction...Four types of unprecedented and chemodivergent reactions betweenα-diketones and alkynylα-diketones have been achieved under the catalysis of phosphine and Br?nsted base,respectively,leading to the rapid construction of four different classes of biologically important but synthetically challenging molecular scaffolds including 2-hydroxyfuran-3(2H)-ones,4-hydroxy-2-oxabicyclo[2.2.1]heptan-3-ones,1,3-diaryl cyclobutanes,and 4-(furan-2(3H)-ylidene)cyclopent-2-enones.The formation of the products includes two novel rearrangement processes,and further transformations on the products can be easily achieved to deliver value-added substances such as highly functionalized cyclopentanes.Moreover,the 2-hydroxyfuran-3(2H)-one products display promising photophysical properties such as green luminescence under UV light and aggregation-induced emission effect,showing the practical application value of this work.The great potential ofα-diketones in both synthetic chemistry and material science has been unambiguously demonstrated.展开更多
Phosphine-catalyzed [4+2] annulations of 2-(acetoxymethyl)buta-2,3-dienoates with α-aminonitriles have been developed, in which a-aminonitriles serve as C, N-bisnucleophilic reaction partners and 2-(acetoxymethyl...Phosphine-catalyzed [4+2] annulations of 2-(acetoxymethyl)buta-2,3-dienoates with α-aminonitriles have been developed, in which a-aminonitriles serve as C, N-bisnucleophilic reaction partners and 2-(acetoxymethyl)buta- 2,3-dienoates as "C4 synthons" respectively. A number of a-aminonitriles could be successfully applied to giving multifunctional desired products using PPh3 as catalyst. This method provides a facile entry to access polysubstituted tetrahydropyridines bearing quaternary carbon centers. The possible reaction mechanism was also proposed.展开更多
A facile synthesis of benzofuro[2,3-c]pyridines has been achieved under mild conditions by using ammonium acetate as the nitrogen source through intramolecular cascade annulation.This reaction could efficiently constr...A facile synthesis of benzofuro[2,3-c]pyridines has been achieved under mild conditions by using ammonium acetate as the nitrogen source through intramolecular cascade annulation.This reaction could efficiently construct pyridine ring and furan ring in one step.Moreover,the key annulation step was demonstrated through dihydrobenzofuran intermediates.展开更多
A solvent-regulated diastereodivergent[3+2]annulation reaction between Morita-Baylis-Hillman carbonates from aryl trifluoromethyl ketones and cyclic sulfonimines is developed under the catalysis of a modified cinchona...A solvent-regulated diastereodivergent[3+2]annulation reaction between Morita-Baylis-Hillman carbonates from aryl trifluoromethyl ketones and cyclic sulfonimines is developed under the catalysis of a modified cinchona alkaloid,furnishing diverse polycyclic products bearing vicinal quaternary stereogenic centers with outstanding enantioselectivity and moderate to high diastereoselectivity.展开更多
Synthesizing ring structure aviation fuels from biomass-derived platform molecules is challenging,especially for bridged ring structure aviation fuels which are typically achieved from fossil-derived chemicals.Herein,...Synthesizing ring structure aviation fuels from biomass-derived platform molecules is challenging,especially for bridged ring structure aviation fuels which are typically achieved from fossil-derived chemicals.Herein,we report the synthesis of a series of ring structure biofuels in two steps by a combination of a solvent-free Michael-cyclization reaction and a hydrodeoxygenation(HDO)reaction from lignocellulosederived 5,5-dimethyl-1,3-cyclohexanedione.These biofuels are obtained with high overall yields up to 90%,which exhibit high densities of 0.81 g cm^(-3)-0.88 g cm^(-3)and high volumetric neat heat of combustion(VNHOC)values of 36.0 MJ L^(-1)-38.6 MJ L^(-1).More importantly,bridged-ring structure hydrocarbons can also be achieved in two steps by a combination of a Robinson annulation reaction and an HDO reaction to afford the final products at high overall yields up to 90%.The bridged-ring structure products have comparable high densities and high VNHOC values to the best artificial fuel JP-10(0.94 g cm^(-3)and 39.6 MJ L^(-1)).The results demonstrate a promising way for the synthesis of high-density aviation fuels with different fuel properties at high yields.展开更多
4-Methyl-2-(4-methylphenyl)-5-(2-thiazolinyl)-1,3-thiazole, a novel compound, was synthesized by the annulation of 5-hydroxyethylcarbamoyl-4-methyl-2-(4- methylphenyl)-1,3-thiazole with P2S5. 5-Hydroxyethylcarba...4-Methyl-2-(4-methylphenyl)-5-(2-thiazolinyl)-1,3-thiazole, a novel compound, was synthesized by the annulation of 5-hydroxyethylcarbamoyl-4-methyl-2-(4- methylphenyl)-1,3-thiazole with P2S5. 5-Hydroxyethylcarbamoyl-4-methyl-2-(4-methylphenyl)-1,3-thiazole was prepared from the starting material of p-tolunitrile. The newly synthesized compounds were characterized by elemental analysis, IR, NMR(^1H, ^13C) and MS spectra. Hence, the crystal of the title compound was obtained, and its structure was determined by X-ray diffraction analysis. The crystal belongs to the triclinic system, space group P1 with a = 7.354(4), b = 8.383(4), c = 11.543(6)A, α = 76.688(6), β = 72.299(6), γ = 88.157(6)°, V = 659.2(6) A^3, Z = 2, Mr = 274.39, Dc = 1.382 g/cm^3, μ = 0.386 mm^-1, F(000) = 288, R = 0.0586 and w R = 0.1808 for 2984 unique reflections with 2213 observed ones(I 〉 2σ(I)). The title compound was also screened for its antibacterial activities against Bacillus subtilis and Escherichia coli. The result indicates that the target compound presents potential antimicrobial activities, and that the minimum inhibitory concentration(MIC) values of the title compound against the two tested strains are both 62.5 μg/mL.展开更多
An uncatalyzed and easily accessible synthetic approach for the preparation of 3-aroylindoles was investigated using nitrosoarenes and aromatic terminal ethynyl ketones. Indole derivatives were produced in good yields...An uncatalyzed and easily accessible synthetic approach for the preparation of 3-aroylindoles was investigated using nitrosoarenes and aromatic terminal ethynyl ketones. Indole derivatives were produced in good yields and excellent regioselectivity. Functionalizations of the indole products were carried out affording highly valuable and versatile compounds. The indolization protocol was studied as a fundamental step for the preparation of pravadoline and 1-butyl-3-(1-naphthoyl)indole (JWH-073), bioactive molecules showing antinociceptic properties.展开更多
A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye photocatalysts.Broad substrate scope and high functional group tolerance wer...A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye photocatalysts.Broad substrate scope and high functional group tolerance were demonstrated by more than 50 examples.The reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.展开更多
基金financially supported by National Key Research and Development Program of China(No.2018YFA0209401)National Natural Science Foundation of China(Nos.22171053,21733003)Natural Science Foundation of Shanghai(No.21ZR1409600)。
文摘Fluoranthenes have attracted tremendous attention due to their unique optoelectronic properties and extensive applications.Although several synthetic methodologies have been developed for the preparation of fluoranthene derivatives,it is still unfavorable to functionalize the fluoranthene framework at different positions due to the relatively low selectivity and reactivity.Herein,a catalyst-free intramolecular[4+2]annulation between thiophenes and alkynes is developed towards the synthesis of fluoranthenes.Altogether 20 examples have been demonstrated using this method.Various functional groups can be precisely introduced into the fluoranthene skeleton at different positions by simply tuning the substituents on the thiophenes and alkynes.The conjugation of the fluoranthene can be facilely extended through different directions.Furthermore,the feasibility of this[4+2]annulation reaction is also investigated by density functional theory calculations.Therefore,this protocol provides not only a synthetic methodology towards fluoranthenes with substituents functionalized at different positions,but also an effective pathway to construct large polycyclic aromatic hydrocarbons containing fluoranthene moieties.
基金the National Natural Science Foundation of China(grant nos.21831007 and 22071229).
文摘The cooperative catalysis of an achiral Lewis base and a chiral N-heterocyclic carbene(NHC)enables a highly enantioselective[4+3]annulation of benzoxazinanones with isatin-derived enals.DMAP serves as a nucleophilic Lewis base to promote decarboxylation of benzoxazinanones,which leads to azaortho-xylylene intermediates that undergo[4+3]annulations with NHC-bound homoenolates.This method breaks the substrate scope limitation of transition-metal-catalyzed variants,thus a broader range of benzoxazinanones are tolerated,and provides a straightforward entry to enantioenriched spirooxindoles in high structural diversity.
基金support from the National Natural Science Foundation of China(21772202,21831008)Beijing Municipal Science&Technology Commission(project No.Z191100007219009)Beijing National Laboratory for Molecular Sciences(BNLMS-CXXM-201901)are gratefully acknowledged.
文摘Conventional reactive sites of ketones with aldehydes lie on the carbonyl andα-carbon positions,which lead to a wide range of classic reactions such as pinacol-coupling and aldol-type condensations.Herein,an unprecedented reactive site of aromatic ketones toward aldehydes has been revealed by using earth-abundant manganese catalysis,which enabled the first deoxygenative[3+2]annulations of ketones and aldehydes through C–H activation affording isobenzofuran derivatives.Mechanistic studies give hints on the dual role of triphenylborane additive in the reaction,that is,promoting C–H activation as a transmetalation reagent and activating aldehydes as a Lewis acid.
基金the National Natural Science Foundation of China(Nos.22071242 and 21871260)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB20000000)+1 种基金Fujian Natural Science Foundation(No.2018J05035)Science and Technology Research Program of the Education Department of Jiangxi Province(No.GJJ1991151)。
文摘Copper-catalyzed divergent annulations betweenα-diketones and alkynylα-diketones have been achieved,delivering a series of highly functionalized and biologically important cis-hexahydro-2Hcyclopenta[b]furan(HCPF)and 2-hydroxydihydrofuran-3(2H)-one(HDFO)products with high levels of stereoselectivity under identical conditions.The protocol features the use of earth-abundant copper catalyst,mild conditions,shortening synthetic routes in constructing different molecular frameworks,and reducing the corresponding possible waste production.The substituents of the nucleophilicα-diketones play crucial roles in switching the reaction pathways.
基金We thank for the financial support from the National Natural Science Foundation of China (Nos. 21421091 and 21432011), the National Basic Research Program of China (973 Program) (2015CB856600), the Natural Science Foundation of Shanghai (17ZR1436900), the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB20000000) and the Youth Innovation Promotion Association CAS (2017301). We thank Dr. Xue-Bing Leng for X-ray crystal analysis
文摘Copper catalyzed enantioselective [4+2] annulations of D-A cyclobutanes and aldehydes have been developed. In the presence of a side arm modified chiral bisoxazoline (SaBOX) ligand, the [4+2] annulations proceeded smoothly with a broad substrate scope. 22 examples were studied, leading to the corresponding products with various functional groups in 41%-99% yields with 〉99/1 dr and 90%-96% ee. The resulting product with two ester groups was mono-reduced, giving the corresponding product in excellent diastereoselectivity without loss of the enantiopurity.
基金the National Natural Science Foundation of China(Nos.21172057,21272058)the Research Fund for the Doctoral Program of Higher Education(No.20114104110005)forfinancial support
文摘In this paper, an efficient synthesis of cyclopentenyl ketones and cyclohexenyl ketones through tertiary phosphine catalyzed [3 + 2] and [4 + 2] annulations of 1,2-allenic ketones with activated alkenes has been developed. Compared with published synthetic methods on cyclopentenyl ketones and cyclohexenyl ketones, the protocols developed in this paper have the advantages such as readily available starting materials, mild reaction conditions and high efficiency.
基金financial support from the NSFC(21572135 and 21321061)
文摘A mild and efficient dearomatic [3+2] annulation reaction of 3-nitro-7-azaindoles and Morita Baylis Hillman carbonates from isatins was developed catalyzed by DMAP, affording the corresponding polycyclic spirooxindoles containing fused azaindoline architectures and vicinal quaternary centers in excellent yields(up to 96%) with high regio- and diastereoselectivity(dr 〉 19:1). Moderate enantioselectivity(79% ee) was obtained by employing a chiral DMAP-type Lewis base catalyst.
基金the National Key Research and Development Program of China(No.2016YFB0401400)the National Natural Science Foundation of China(Nos.21871163 and 22071134)。
文摘Me OTf-catalyzed formal[4+2]annulation of styrene oxides with alkynes to afford polysubstituted naphthalenes has been realized,which undergoes sequential electrophilic cyclization/ring expansion.A range of substrates were tolerated in the formation of naphthalene derivatives with high regioselectivity in satisfactory yields.The reaction could also be carried out on gram scale.
基金Acknowledgement Financial support from National Natural Science Foundation of China (Nos. 21072100 21121002 21272119) is gratefully acknowledged.
文摘in this work, the phosphine-catalyzed annulation reactions between modified allylic derivatives and polar 1,1-dicyano-1,3-dienes have been studied. In the catalysis of PPh3 (20 mol%), a [4 + 1 ] annulation reaction is realized between a series of l,l-dicyano-2,4-diaryl-1,3-dienes and ethoxycarbonyl-activated allylic acetate, producing polysubstituted cyclopentenes in modest to excellent yields. It is also observed that the substituents of both 1,3-dienes and allylic derivatives have a significant influence on the annulation mode: under the catalysis of PPh3 or PBu3 (20 mol%), regioselective [3 + 2] annulation products are formed from differently substituted substratcs.
基金This work was supported by the National Natural Science Foundation of China(21871260,22071242)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB20000000)+2 种基金Fujian Natural Science Foundation(2018J05035)the China Postdoctoral Science Foundation(2018M630734)the Science and Technology Research Program of the Education Department of Jiangxi Province(GJJ1991151).
文摘Four types of unprecedented and chemodivergent reactions betweenα-diketones and alkynylα-diketones have been achieved under the catalysis of phosphine and Br?nsted base,respectively,leading to the rapid construction of four different classes of biologically important but synthetically challenging molecular scaffolds including 2-hydroxyfuran-3(2H)-ones,4-hydroxy-2-oxabicyclo[2.2.1]heptan-3-ones,1,3-diaryl cyclobutanes,and 4-(furan-2(3H)-ylidene)cyclopent-2-enones.The formation of the products includes two novel rearrangement processes,and further transformations on the products can be easily achieved to deliver value-added substances such as highly functionalized cyclopentanes.Moreover,the 2-hydroxyfuran-3(2H)-one products display promising photophysical properties such as green luminescence under UV light and aggregation-induced emission effect,showing the practical application value of this work.The great potential ofα-diketones in both synthetic chemistry and material science has been unambiguously demonstrated.
基金Supported by the National Natural Science Foundation of China(No. 21372096).
文摘Phosphine-catalyzed [4+2] annulations of 2-(acetoxymethyl)buta-2,3-dienoates with α-aminonitriles have been developed, in which a-aminonitriles serve as C, N-bisnucleophilic reaction partners and 2-(acetoxymethyl)buta- 2,3-dienoates as "C4 synthons" respectively. A number of a-aminonitriles could be successfully applied to giving multifunctional desired products using PPh3 as catalyst. This method provides a facile entry to access polysubstituted tetrahydropyridines bearing quaternary carbon centers. The possible reaction mechanism was also proposed.
基金This work was financially supported by the Natural Science Foundation of Henan Province(No.132300410319)and Luoyang Normal University.
文摘A facile synthesis of benzofuro[2,3-c]pyridines has been achieved under mild conditions by using ammonium acetate as the nitrogen source through intramolecular cascade annulation.This reaction could efficiently construct pyridine ring and furan ring in one step.Moreover,the key annulation step was demonstrated through dihydrobenzofuran intermediates.
基金We are grateful for the financial support from the NSFC(Nos.21931006 and 21921002)the Fundamental Research Funds for the Central Universities.
文摘A solvent-regulated diastereodivergent[3+2]annulation reaction between Morita-Baylis-Hillman carbonates from aryl trifluoromethyl ketones and cyclic sulfonimines is developed under the catalysis of a modified cinchona alkaloid,furnishing diverse polycyclic products bearing vicinal quaternary stereogenic centers with outstanding enantioselectivity and moderate to high diastereoselectivity.
基金financial support from the National Natural Science Foundation of China (grant number: 51876151)the Fundamental Research Funds for the Central Universities, the World-Class Universities(Disciplines)+3 种基金the Characteristic Development Guidance Funds for the Central Universities (grant number: PY3A010)the start-up funding from Xi’an Jiaotong University (grant number: QY1J003)supported by the HPC platform, Xi’an Jiaotong Universitythe support of H2 Cluster in XJTU
文摘Synthesizing ring structure aviation fuels from biomass-derived platform molecules is challenging,especially for bridged ring structure aviation fuels which are typically achieved from fossil-derived chemicals.Herein,we report the synthesis of a series of ring structure biofuels in two steps by a combination of a solvent-free Michael-cyclization reaction and a hydrodeoxygenation(HDO)reaction from lignocellulosederived 5,5-dimethyl-1,3-cyclohexanedione.These biofuels are obtained with high overall yields up to 90%,which exhibit high densities of 0.81 g cm^(-3)-0.88 g cm^(-3)and high volumetric neat heat of combustion(VNHOC)values of 36.0 MJ L^(-1)-38.6 MJ L^(-1).More importantly,bridged-ring structure hydrocarbons can also be achieved in two steps by a combination of a Robinson annulation reaction and an HDO reaction to afford the final products at high overall yields up to 90%.The bridged-ring structure products have comparable high densities and high VNHOC values to the best artificial fuel JP-10(0.94 g cm^(-3)and 39.6 MJ L^(-1)).The results demonstrate a promising way for the synthesis of high-density aviation fuels with different fuel properties at high yields.
基金supported by the Open-end Funds of Jiangsu Key Laboratory of Marine Biotechnology,Huaihai Institute of Technology(2013HS004)Open-end Funds of Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening(2015HYB05)a project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(201402)
文摘4-Methyl-2-(4-methylphenyl)-5-(2-thiazolinyl)-1,3-thiazole, a novel compound, was synthesized by the annulation of 5-hydroxyethylcarbamoyl-4-methyl-2-(4- methylphenyl)-1,3-thiazole with P2S5. 5-Hydroxyethylcarbamoyl-4-methyl-2-(4-methylphenyl)-1,3-thiazole was prepared from the starting material of p-tolunitrile. The newly synthesized compounds were characterized by elemental analysis, IR, NMR(^1H, ^13C) and MS spectra. Hence, the crystal of the title compound was obtained, and its structure was determined by X-ray diffraction analysis. The crystal belongs to the triclinic system, space group P1 with a = 7.354(4), b = 8.383(4), c = 11.543(6)A, α = 76.688(6), β = 72.299(6), γ = 88.157(6)°, V = 659.2(6) A^3, Z = 2, Mr = 274.39, Dc = 1.382 g/cm^3, μ = 0.386 mm^-1, F(000) = 288, R = 0.0586 and w R = 0.1808 for 2984 unique reflections with 2213 observed ones(I 〉 2σ(I)). The title compound was also screened for its antibacterial activities against Bacillus subtilis and Escherichia coli. The result indicates that the target compound presents potential antimicrobial activities, and that the minimum inhibitory concentration(MIC) values of the title compound against the two tested strains are both 62.5 μg/mL.
基金The authors gratefully acknowledge financial support from the National Natural Science Foundation of China(No.39370809)National New Drug Foundation(No.92-08-N).
文摘AF-5 was synthesized through a convergent method. The key step was the Robinson annulation using a key intermediate pentyl vinyl ketone.
文摘An uncatalyzed and easily accessible synthetic approach for the preparation of 3-aroylindoles was investigated using nitrosoarenes and aromatic terminal ethynyl ketones. Indole derivatives were produced in good yields and excellent regioselectivity. Functionalizations of the indole products were carried out affording highly valuable and versatile compounds. The indolization protocol was studied as a fundamental step for the preparation of pravadoline and 1-butyl-3-(1-naphthoyl)indole (JWH-073), bioactive molecules showing antinociceptic properties.
基金financial support of this research by the National Natural Sciences Foundation of China(21871044 and 21472017).
文摘A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye photocatalysts.Broad substrate scope and high functional group tolerance were demonstrated by more than 50 examples.The reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.